Why Do So Many People With Thyroid Conditions Have Dry Eyes?
Published February 23 2015
One of the most common symptoms I see in people with both hypothyroid and hyperthyroid conditions is dry eyes. And while this usually isn’t the most severe symptom in the majority of patients, it’s still something which is quite bothersome. Many of these people resort to using eye drops, but very rarely is the cause of the dry eyes addressed.
But why do so many people experience dry eyes? Well, the lacrimal gland is what’s responsible for the secretion of tears, and these tears of course help to moisten and lubricate the eye. And there are numerous factors which can affect the lacrimal gland. The meibomian glands (tarsal glands) can also be involved, as they are a type of sebaceous gland, and dysfunction of these glands can also cause dry eyes.
What I’d like to do is discuss some of the more common causes of dry eyes:
Inflammation. It is understood that dry eye syndrome is due to inflammation of the ocular surface and lacrimal gland, neurotrophic deficiency and meibomian gland dysfunction (1). Autoimmune conditions resulting in proinflammatory cytokines can also result in dry eyes, such as Sjogren’s syndrome (2), and in thyroid-associated ophthalmopathy (3). Another study I came across showed that dry eyes is caused by an imbalance in the protective immunoregulatory and proinflammatory pathways of the ocular surface (4). While taking artificial tears can sometimes help with the symptoms, this obviously won’t do anything to control the inflammation.
Environmental conditions. Certain environmental conditions can lead to dry eyes. Smoking cigarettes can lead to dry eyes (5) (6). A low relative humidity can also cause dry eye disease (7). Exposure to sun, dust, and wind exacerbate or precipitate dry eye disease (8). Even intense computer work can lead to eye dryness (9).
Hormone imbalance. Thyroid hormones affect the lacrimal gland and the ocular surface (10), and this might explain why hypothyroidism can lead to dry eyes. However, the sex hormones also have an effect on tear secretion (11). Chronic androgen deficiency is associated with meibomian gland dysfunction (12). Some studies show that women who take estrogen are at an increased risk of dry eye syndrome (13).
Other health conditions. Other conditions are associated with dry eyes. One study involving 72 patients with rheumatoid arthritis showed that dry eyes always should be taken into consideration when someone has rheumatoid arthritis (14). Another study involving 199 patients with type 2 diabetes showed that diabetes and dry eyes appear to have a common association (15). Blepharitis involves inflammation of the eyelids, and is also associated with dry eyes.
Eye surgery and contact lenses. Contact lenses and corneal refractive surgery can also affect the lacrimal gland and lead to dry eyes (16) (17). In fact, this is one of the main reasons I personally have been hesitant to get laser surgery done over the years, as while I would love to not rely on glasses or contact lenses, laser surgery can potentially cause damage to the sensory nerves in the ocular surface, which can result in decreased tear secretion and dry eye syndromes (17). Although many people have received laser surgery without any problems, and symptoms of dry eyes are usually transient, I personally know a few people who received this procedure and after a few years still have chronic and severe dry eyes. Cataract surgery can also lead to dry eye syndrome (18).
Certain medications. A few studies have shown that using systemic and oral antihistamines can result in dry eyes (19) (20). Taking antidepressants can also cause dry eye disease (21) (22). Taking antihypertensive medication can also cause or exacerbate dry eyes (23) (24).
Dry Eye Syndrome and Natural Treatment Methods
Unfortunately the conventional medical approach involves giving the patient artificial tears, or to give medications such as corticosteroids (25) or Cyclosporine A (26) to help with the inflammation. Antibiotics are also given at times (27). Not only do these drugs not do anything to address the cause of the condition, but they of course can also cause side effects. While it might be necessary for people with dry eyes to take lubricating eye drops, if at all possible the cause of the condition should be addressed.
So what can be done naturally to help with dry eyes? Well, if the dry eyes are caused by certain environmental conditions or medications, then the obvious goal should be to remove the factor which may be causing it. For example, if someone works in a low humidity environment, or spends all day in front of a computer, then these factors need to be addressed. If the dry eyes began upon taking a certain medication (i.e. oral contraceptives), then it would be a good idea to run this by your medical doctor. If the dry eyes were caused by a surgical procedure such as LASIK surgery then as far as I know there isn’t any permanent solution to correct the eye dryness.
On the other hand, if the dry eyes were caused by a hormone imbalance and/or inflammation, then this can be corrected in most cases. With regards to inflammation, the goal should be to detect and then remove the factor which is causing the inflammation, and giving certain nutrients and herbs can help such as vitamin D3, fish oils, and turmeric. These also will help to increase regulatory T cells, which can be important if the dry eyes is caused by an autoimmune process.
In summary, there are numerous factors which can cause dry eyes. In people with thyroid and autoimmune thyroid conditions, two of the main factors responsible for dry eyes include a thyroid hormone imbalance and/or an increase in inflammation. However, other factors can cause or contribute to dry eyes, such as an imbalance of the sex hormones, a low relative humidity, cigarette smoking, intense computer work, wearing contact lenses, and certain medications such as antihistamines and antidepressants. A natural treatment approach to dry eyes should involve removing the factor which may be causing the problem, and if a hormone imbalance and/or inflammation is responsible then these need to be addressed.